McCarthy, currently EPA's assistant administrator for the office of Air and Radiation, is widely thought to have excellent credentials for the post. Those creds include her stint as commissioner of the Connecticut Department of Environmental Protection.

"This obstructionism by Republican senators is paralyzing partisanship at its worst," a clearly nettled Blumenthal said Friday. "I have worked with her closely -- under a Republican governor whom she served with tremendous fidelity to both environmental and economic values."

"It's outrageous that the Senate Republicans are again blocking the nomination of an extremely qualified candidate," Murphy said. "Over the course of her distinguished career in both Connecticut and Massachusetts, Gina McCarthy built a reputation for working with Republicans and Democrats alike "the work of the EPA is too important to be hamstrung by a handful of senators playing political games."

On Thursday, all eight Republicans on the Senate Committee on Environment and Public Works boycotted a scheduled vote on McCarthy's confirmation, saying they were "completely unsatisfied" with her answers on some topics -- after the eight asked her more than 1,000 questions.

Murphy pointed out that McCarthy served then-Massachusetts Gov. Mitt Romney as an adviser on environmental policy. "If he had won the presidency and picked her to run the EPA, would the GOP block her nomination? Of course not," he said in a statement.

"Republicans in the Senate need to stop looking at every vote as an opportunity to score political points against the president," Malloy said bluntly. "The election is long over. It's time for them to do their jobs."

Recognizing that even if the angered Democrats are somehow able to move the nomination out of committee, it would doubtless need a filibuster-proof 60-vote margin to succeed, some are using the case as a prime example of why the filibuster rules need to be changed, at least for the approval of presidential appointments.